Attending with the development of touch control technology, the touch control devices have been progressed from the physical keypads of traditional cell phones to the virtual keypads integrated with the touch panel of the smart phones, which make communication of the human-computer interface more convenient and user's friendly. There are many types of touch control technologies. For the touch control technology used in small to medium size touch control devices (such as cell phones, tablets, notebooks, and etc.), the main trend has been shifted from the conventional externally combined touch panel (TP) to the in-cell touch panel (ITP). In addition, in order to implement additional touch control functions, the touch control functions, such as Force Touch, fingerprint identification, and etc., have been integrated into the in-cell touch panels. In present, 2D display technology still dominates the display market and so does the 2D touch control technology. However, attending with the development and mature of 3D display technology, 3D holographic technology will become the main trend in the future and the applications of floating touch will be expanded. Accordingly, the research of floating positioning technology is particularly important.